Calcitonin exon sequences influence alternative RNA processing.
The pre-mRNA encoding calcitonin (CT) and CT gene-related peptide (CGRP) is differentially processed in a tissue-specific fashion to include exon 4 (which encodes CT) or exclude this exon and splice to exon 5 (which encodes CGRP). We have used a CT-specific in vitro RNA-processing system to identify cis-acting sequences required to prevent splicing to exon 5. Deletion mapping demonstrated the presence of an element within the first 45 nucleotides of the CT-specific exon 4 that was required to suppress splicing to the CGRP-specific exon 5. This element was able to function in a completely heterologous system to suppress splicing when the CGRP exon was replaced with a constitutive viral exon. The element was unable to suppress splicing in the absence of a proximal CT-specific 3' splice site. Our results suggest that CT-specific splicing requires assisted recognition of its 3' splice site.
Cote
G J
GJ
Department of Medicine, Veterans Administration Medical Center, Houston, Texas.
Nguyen
I N
IN
Berget
S M
SM
Gagel
R F
RF
D002116:Calcitonin / Q000235:genetics*; D015740:Calcitonin Gene-Related Peptide / Q000235:genetics*; D002872:Chromosome Deletion; D005091:Exons; D005786:Gene Expression Regulation / Q000187:drug effects; D006367:HeLa Cells; D006801:Humans; D012323:RNA Processing, Post-Transcriptional; D012326:RNA Splicing; D012333:RNA, Messenger / Q000378:metabolism*; D012045:Regulatory Sequences, Nucleic Acid
D012333:RNA, Messenger; D002116:Calcitonin; D015740:Calcitonin Gene-Related Peptide